Reversing-gear for multiple-expansion steam-engines.



' J. G; MAXWELL. REVERSING GEAR FOR MULTIPLE EXPANSION STEAM ENGINES.

APPLICATION IILED 00125, 1912.,

Patented Nov. 11, 1913.

3 SHEETSSHEET 1 Allorlmy WITNESSES if-eazzmdfl" J. G. MAXWELL. REVEBSING GEAR FOR MULTIPLE'EXPANSION STEAM ENGINES. APPLIOATION FE'ILED 0OT.26, 1912.

3 SHEBTSSHEET 2.

. (I I I I WITNESSES v INVENTOR ZLS. 910119117 (3% aqcpfififilaxwll A, j V Allarmy J. G. MAXWELL. REVERSING GEAR FOR MULTIPLE EXPANSION STEAM ENGINES. APPLICATION FILED 00125, 1.912.

Patented Nov. 11, 1913.

3 SHEETS-SHEET 3.

Z??? Z L 4,15 6% 6. WZifik A. $0 SB G V Atlarnej J G. 0F BROOKLYN, NEW YORK.

REVERSING-GEAB, F013, MULTIPLE-EXPANSIQN STEAM-ENGINES.

Specification of Letters Patent.

Patented Nov. 11, 1913.

Application filed October 25, 1912. Serial l qo. 727,7 46.

To all whom 2'25 may concern:

Be it known that I, Josnrrr G. MAXWELL', a

citizen of the UnitedSta'tes of America,

residing at Brooklyn, in" the "coi nty of Kings and State of New York, have invented certain new and useful lnipro vements'in Reversing Gear for Multiple --Expansion -En of which the renew gspecification.

My invention relates to reversing gears for multiple expansion and componnd steam englnes and its ob1ect 1s to ellmlnate the complicated mass of machinery heretofore necessary and substitute therefor a simple,

compact, and eflicient mechanism.

As showin a specific embodiment of my 1nvent1on re erence 1s inade to thedraJw-- v ings forming part of the spec ficat onlnj which Figure 1 is a top plan View of the of my reversing gear showing the h gh? pressure eccentr c attached. Fig. 21s a view 1 of the interior of the reversing cylinder with the fixed piston and shaft" in section to show the means of attachingthe fornier. Fig. 3 is 120 section of the sleeve 7) awing the steam ducts. Fig. 4 is a sideIelevation ofthe steam chest showing the valve mechanism in dotted line. Fig. 5 is aplan view of the contact face of the valve and Fig. .6 is a section on the line 4 4 o fFigI5. Fig. 7 isa top plan view of the valve" seat.

Figs, 8, .9 and 10 are detail'siofthe low pressure eccentric. Fig. 11 is aside elevation of my reverse gear attached to a" compound engine. Fig. '12 is a rear elevation' .of the same showing the steam ches't in position.

The following is -brief description of the drawings in which like characters denote like parts A is the reversing cylinder containing the fixed piston 70 around i which it rotates through an angle of "120. It isjclosed by two 'cylindenheads I?) i and" 0' 'removably mounted on the cylinder; The cylinder head 0 is made in one piece with the'sleeye 0 .to which the high pressure eccentric QcZ bearing the strap d and rod d is directly attached. The head I) 'is made in onep iece with the sleeve 1) which has a jacket 6 covering it. Within the sleeve "6' are the grooves or passages f and f which by means of the ducts ia'nd 3' respectively convey the steam to the reversing'gear. The pa nt being fixed by means of the'pin to shaft h, the steam forcing against the partitionfa causes the cylinder to rotate through an angle of 120 carrying with it the high pressure eccentric Z. The cylinder a has a steam chest '1" connected by means of the pipes m and m. Steamentering the chest through the pipe 2 passes through the passage a, in the valve into the openings to .aiidEu in the yalve seat as may be directed by tlieoper'ator by means of the shaft t, set into a boss on the valve tand joined by a'set screw, at Jone end and having at the other the handle t If the handle be turned so the opening a in the valve 2? is over the opening w in the valve seat, the steam passes through the valveat a into the seat at o and through the seat by means'of the passage to theYpipe mYa-nd into the passage f i and so to the cylinder as described above.

Whenthe valve is in this position the steam groove 0 connects the opening a with the exhaust port a which it will be seen is much smaller than the inlet ports. Thus the steam elre'a'dy'in the space, shown in Fig. 2 but not ndicated a character exhausting through thepassagej isrestricted'at w andacts as a cushion to prevent shock in reversing.

The low pressure eccentric a carrying the strap a and 150d 2? is self reversing'having a slot 2 in 'whiizh an enlargementor shoulder h uponthe shaft engages allowing it to rotate through an angle of 120. It is held from slipping by plates 1/ bolted upon the sides, and engaging the end of the shoulder h.

The complete operation of the gear is as follows'z Steam is admitted to the steam chest 9]" by means ofjth'e pipe 2. Its admission to the ports m, m" is governed by the long stemmed valve 2?. If steam is ad initted'to the port on it passes through the sleeve 6 into the peripheral groove f in the sleeve 6, thence through the passage z into the space i" in the cylinder 42. The pressure of the steam (the piston 70 being fixed to the shaft) forces the cylinder a to rotate until the formerly disengaged wall of the piston engages the formerly disengaged wall of the cylinder partition, the rotation taking place through an angle of 120. The high pressure cylinder being fixed to the cylinder at, by ineans of theh'ead c and the sleeve 0 rotates "therewith and is swung into a reversed position. In this manner one cylinder (ina compound engine the high presssure) is reversed. The other being provided with self reversing eccentrics may be re versed by admitting steam to the reversed cylinder and allowing the engine to run.

It will be seen by' those skilled in the art that this device may be attached not only to any multiple expansion engine. but to any engine having eccentrically operated valves and'that many changes may be made wit-h out changing the letter of the invention.

Having now described my invention what I claim and desire to secure by Letters Patent is: V

1. In a reversing gear for multiple expansion steam engines the combination of a high pressure eccentric, means for reversing same eccentric comprising a cylinder mounted on the shaft of said'engine and adapted to rotate with the same, a pair of cylinder heads on .said cylinder, a short sleeve cast in one piece with one of saidcylinderheads and adapted toengage the high pressure eccentric, means forrotatably shifting said cylinder through an angle of about 120 With relation to the shaft comprising a fixed piston and a partition within said cylinder means for admitting steam to the cylinder oneither side of the piston so as to bring the formerly disengaged. wall of said partition into contact with the formerlydisengaged wall of the piston, means for preventing shock in. the contact comprising a steam cushion formed by the reduction of the exhaust port thus restricting the escape of the steam from the space in the cylinder and a self reversing low pressure eccentric substantially as described.

' 2. In a reversing gear for multiple expansion steam enginesthe combination of a high pressure eccentric means for reversing said eccentric comprising a cylinder mounted on the shaft of said engine and adapted to rotate with the same, a pair of cylinder heads on said cylinder, sleeves cast upon said cylinderheads means for attaching one of the sleeves to the high pressure eccentric, a cover on the other sleeve means for making said cover steam-tight, means for introducing steam to said second sleeve and means embodied in the sleeve for conducting said steam to the cylinder means for rotatably shifting said cylinder through an angle of l20 'with relation to the shaft comprising a piston and a partition within said cylinder, means for fixing said piston to said shaft, comprising a pin extending into said piston and adapted to engage in said shaft and means for admitting said steam to the cylinder on either side of the piston so as to bring the formerly disengaged wall of said partition into contact with the formerly disengaged Wall of the piston, means for preventing shock in the contact comprising a steam cushion formed by the reduction of the exhaust port thus restricting the escape of the steam from the space in the cylinder and a self reversing low pressure eccentric substantially as described.

8. In a reversing gear for multiple expansion steam engines the combination of a high pressure eccentric means for reversing said eccentric comprising a cylinder mounted on the shaft of said engine and adapted to 1'0- tate with the same, a pair of cylinder heads on said cylinder sleeves cast upon said cylinder heads means for attaching one of said sleeves to the high pressure eccentric, means for introducing steam to said cylinder through the second sleeve comprising a pair of parallel grooves in said sleeve-ports in said grooves, said ports connecting with passages leading to the cylinder, a cover for said second sleeve, means embodied in the sleeve for insulating said grooves, means for introducing steam to either of said grooves and connecting the other with the exhaust, means for rotatably shifting said cylinder through an angle of 120 with relation to the shaft comprising a piston. and a partition within said cylinder, means for fixing said piston to said shaft comprising a pin extending into said piston and adapted to engage in said shaft, said passages entering the cylinder on. either side of the piston so as to bring the formerly disengaged Wall of said partition into contact with the formerly disengaged wall of the piston, means for preventing shock in the contact comprising a steam cushion formed by the reduction of the exhaust port thus restricting the escape of the steam from the space in the cylinder and a self reversing low pressure eccentric substantially as described.

4. In a reversing gear for multiple expansion steam engines the combination of a high pressure eccentric, means for reversing said eccentric comprising a cylinder mounted on the shaft of said engine and adapted to retate with the same, a pair of cylinder heads on said cylinder sleeves cast upon said cylinder heads means for attaching one of said sleeves to the high pressure eccentric, means for introducing steam to said cylinder through the second sleeve comprising a pair of parallel grooves in said sleeve ports in said grooves said ports connecting with passages leading to the cylinder, a cover for said second sleeve, means embodied in the sleeve for insulating said grooves, means for introducing steam to either of said grooves, and connecting the other with the exhaust comprising a steam chest, means for introducing steam thereto, a valve and a valve seat within said steam chest, a port extending through said valve and steam groove diametrically opposite said port and extending slightly past the center of contact face thereof, a pair of diametrically opposite inlet ports and a centrally located exhaustport in the valve seat, said exhaust port being smaller than amazes said inlet ports, means for connecting said inlet ports with the grooves, means for connecting the port in said valve with one of the inlet ports in which case said steam groove connects the second with the exhaust port, means for rotatably shifting said cylinder through an angle of 120 with relation to the shaft comprising a piston and a partition within said cylinder, means for fixing said piston to said shaft comprising a pin extending into said piston, and adapted to engage in said shaft, said passages entering the cylinder on either side of the piston so as to bring the formerly disengaged wall of said partition into contact with the formerly disengaged wall of the piston, means for preventing shock in the contact comprising a steam cushion formed by the reduction of the exhaust port thus restricting the escape of the steam from the space in the cylinder, and a self reversing low pressure eccentric substantially as described.

5. In a reversing gear for multiple expansion steam engines the combination of a high pressure eccentric, means for reversing said eccentric comprising a cylinder mounted 011 the shaftof said engine and adapted to rotate with the same, a pair of cylinder heads on said cylinder sleeve cast upon said cylinder heads means for-attaching one of said sleeves to the high pressure eccentric, means for introducing steam to said cylinder through the second sleeve comprising a pair of parallel grooves in said sleeve ports in said grooves said ports connecting with passages leading to the cylinder, a cover for said second sleeve, means embodied in the sleeve for insulating said grooves, means for introducing steam to either of said grooves, and connecting the other with the exhaust comprising a steam chest, means for introducing steam thereto, a valve and a valve seat within said steam chest, a port extending through said valve and steam groove diametrically opposite said port and extending slightly past the center of contact face thereof, a pair of diametrically opposite inlet ports and a centrally located exhaust port in the valve seat, said exhaust port being smaller than said inlet ports, means for connecting said inlet ports with the grooves, means for connecting the port in said valve with one of the inlet ports in which case said steam groove connects the second with the exhaust port, means for rotatably shifting said cylinder through an angle of 120 with relation to the shaft comprising a piston and a partition within said cylinder, means for fixing said piston to said shaft comprising a pin extending into said piston, and adapted to engage in said shaft, said passage entering the cylinder on either side of the piston so as to bring the formerly disengaged wall of said partition into contact with the formerly disengaged wall of the piston, meansfor preventing shock inthe contact comprising a, steamcushion formed by the reduction of the exhaust port thus restricting the escape of the steam from the space in the cylinder, means for making the low pressure eccentric self reversing comprising a groove extending through 120 in the shaft-bearing face of said low pressure eccentric a key formed on said-shaft and normally adapted to engagesaid eccentric and swing free through said groove to 120 when the engine is reversed and means for holding said eccentric from longitudinal movement on the shaft comprismg a pair of plates bolted to said eccentric and adapted to engage the ends of said key.

6. A reversing gear for steam engines having eccentrics, comprising a cylinder mounted on the eccentric bearing shaft of said engine and attached to one of said eccentrics and adapted to reverse the same, the remainder of said eccentrics being self reversing.

7 Ina reversing gear for steam engines having eccentrics, the combination of a cylinder for reversing one of said eccentrics mounted on the eccentric bearing shaft of the engine and having its piston aflixed thereto and selfreversing eccentrics as described.

8. In a'reversing gear for steam engines, having eccentrics the combination of means carried by the eccentric bearing shaft of the engine for reversing one of the eccentrics, with other eccentrics adapted to automatically shift on the shaft through an angle sufficient to reverse the same.

9. In a reversing gear for steam engines, having eccentrics the combination of one of the eccentrics of the engine, of a cylinder for reversingsaid eccentric mounted on the eccentric bearing shaft of the engine, and self reversing eccentrics as described.

, .10. A reversing gear for multiple expan sion steam engines having eccentrics, com-- prising, the combination with the engine of acylinder mounted on the eccentric bearing shaft of said engine adapted to reverse the high pressure eccentric thereof and self reversing low pressure eccentrics as described.

11. A reversing gear for steam engines having eccentrics comprising a cylinder mounted on the eccentric bearing shaft and attached to one of said eccentrics, means for shifting said cylinder with relation to said shaft through an angle sufficient to reverse said eccentric, the remainder of said eccentric being self reversing.

12. A reversing gear for steam engines having eccentrics, comprising a cylinder mounted on the eccentric bearing shaft of the engine, and attached to one of said eccentrics, means for shifting said cylinder through an angle of 120 and thereby re tact with the normally disengaged wall of versing said eccentric, comprising apartithe piston and self reversing eccentrics as tion and a piston Within said cylinder, said described.

piston being affixed to said shaft, one Wall In testimony whereof I aflix my signa- 5 0; said piston normally epgaging one Wall ture in presence of tWo Witnesses.

0 said partition orts or said cylinder 7 whereby steam may be introduced interme- JOSEPH MALVVELL' diate the engaged walls, of said piston and Witnesses:

partition, whereby the normally disengaged DANIEL MoBRIDE,

I 10 Wall of the partition is brought into con- MARY C. MAXWELL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

